AQUATIC ECOLOGY AQUATIC LIFE ZONES: TYPES OF ORGANISMS: SALTWATER (MARINE) Ecosystems: Estuaries, coastlines, coral reefs, coastal marshes, mangrove swamps, continental shelf, & deep ocean AQUATIC Ecosystems: Lakes and Ponds, Streams and Rivers, and Inland wetlands TYPES OF ORGANISMS: Plankton – free floating (or weak swimmers) (phytoplankton – primary producers & zooplankton – primary consumers) Nekton – strong swimmers (fish, turtles, whales) Benthos – bottom dwellers (oysters, barnacles, crustacean, worms) Decomposers – mostly bacteria

SALINITY & TEMPERATURE DETERMINE THE DISTRIBUTION OF THE OCEANIC REALMS

Adaptations for Floating Physical & Chemical Characteristics Water provides buoyancy = physical support, reduces the need for large supporting structures of trunks and legs, helps aquatic organisms move vertically Water provides consistency = keeps organism from drying out or requiring water, constant temperature range Water provides readily dissolved nutrients – b/c water is the universal solvent the nutrients are ready for uptake by primary producers Water provides constant flux – like wind terrestrially, water gives constant circulation and disperses organisms and their larvae & dilutes toxins Adaptations for Floating

Abyssal Primary Productivity No primary producers – many organisms rise to the euphotic zone at night to feed Abyssal Very little nutrients (marine snow) ~250, 000 named organisms

Coastal zone makes up only <10% of the ocean and contains 90% of all marine organisms Diversity of organisms in each layer is determined by: 1) temp 2) sunlight 3) dissolved oxygen 4) nutrients (dissolved CO2 to from carbonate ions for shells), nitrates, phosphates

ESTUARIES/Salt Marsh Ecological and Economic Benefits Partially enclosed area of coastal water where freshwater & silt from rivers meets the sea. High productive area Temperature & Salinity vary daily rhythms of the tides, seasonally with river input fluctuations, and with unpredictable storms Serves as a breeding ground form any organisms (waterfowl, marine organisms) Chesapeake Bay Filtrates sediments, excess nutrients and pollutants BAYS, SOUNDS, & INLETS Acts as a buffer to inland areas during storms

Lie along the coast line in estuaries and intertidal communities of the tropics and subtropics. Mangroves provide habitat form many organisms & reduce long term beach erosion mangroves Act as a filtering system – especially for heavy metals that settle into the anoxic soil below Adaptations to live in anoxic / nutrient poor soil; marine water conditions; & limited supply of freshwater Leaves secrete excess salts Pneumatophores –”roots” for uptake of gases

DUNE SYSTEMS Vegetation is crucial for the success of the dune system Construction & Development should ideally be behind the secondary dune system Economically dunes are important in the reduction of storm surge damage to coastal development

Barrier Island Systems Helps protect main land development. Also protects coastal dunes & estuary systems.

CORAL REEF DYNAMICS Most biologically diverse aquatic system (niche availability) Three categories of organisms 1) sessile – attached organisms 2) borrowing organisms 3) fishes Live between 18°C to 30°C (even one degree above that can trigger bleaching) Coral Reefs exist in low nutrient waters (oligotrophic) and therefore rely on an endosymbiotic algae (zooxanthellae) to provide nutrients Photomicrograph of algae clusters in coral polyp

Hydrothermal Vent Communities - abyssal plains Ecosystem that survives without sunlight! Primary producers = chemosynthetic bacteria Bacteria use sulfur compound to synthesize energy Clams & Tubeworms either eat bacteria or harbor them in their body to supply themselves with “food” Click on the NOAA bar at a the bottom of slide during slideshow to hyperlink to NOAA video clips of vent submersible exploration